Alternative organic wastes as substrates and its impact on growth, proximate chemical and mineral composition of black soldier fly (Hermetia illucens) larvae for subsistent animal feed

ABSTRACT This study explored the growth parameters and nutritional composition of Black soldier fly larvae (BSFL) reared on some selected alternative organic waste materials. The substrates comprised wheat bran (WB) as the control, millet waste (MW), restaurant leftovers (RL) and fruits waste (FW) and were replicated 8 times in a mini-insectary set-up. Proximate nutrient and mineral composition of the larvae were analyzed. RL had the highest (p < 0.0001) total weight of larvae, number of larvae, efficiency of conversion and substrate reduction index compared to the other substrates. Crude protein (%) content of the BSFL was superior (p < 0.000) in the WB and MW substrate groups at 41.1% and 41.4%, respectively. Crude protein and dry matter yield (g) of the BSFL was higher (p < 0.0001) in the RL than in the other substrates. Metabolizable energy and dry matter were superior (p < 0.0001) in MW and RL groups respectively to all the other substrate groups. RL recorded the lowest (p < 0.0001) phosphorus and calcium levels relative to the other substrates. Conclusively, the crude protein content of the BSFL irrespective of the substrates was adequate to be employed in the livestock feed industry.